The present invention relates to storage and transport containers for radioactive materials used for medical treatments, including a novel handle structure for such containers.
While there are a variety of ways in which radioactive materials may be used in various medical treatment applications, in one such treatment application small pellet-like seeds which comprise radioactive material are arranged in a spaced relationship along the length of a ribbon-like member, which ribbon-like member may be cut to any desired length and inserted into a catheter-like surgical tube or needle which is inserted into body tissue to accommodate such implantations of radioactive treatment materials. Such so-called ribbons of radioactive seeds are constructed, in at least one embodiment, by placing pellet-like seeds comprising radioactive material with or without alternate spacing material within a small flexible tube, such as a tube of nylon or teflon plastic material. Those inserts are sufficiently tightly fitting within the tubular envelope that when complete the pellets and spacers maintain their positions within the tube which then has a symmetrically spaced ribbon-like appearance, any desired length of which may be cut and implanted for radioactive medical treatment purposes.
However, it will be appreciated that such radioactive materials must be handled in containers which protect both patients and medical personnel administering such materials to patients. Furthermore, such materials must be safely packaged for transport from manufacturer to distributor to end user, and even within the facility of an end user such as a hospital. It is for the safe storage and transportation of such ribbons of radioactive medical treatment materials that the advantageous storage and transport containers of the present invention are particularly suited.
Containers or vessels for the storage and transportation of radioactive materials such as radioactive waste or radioactive fuel elements associated with nuclear power generation are known in the art as disclosed in Baatz U.S. Pat. No. 4,626,402; Kugeler U.S. Pat. No. 4,634,875 and Waltersdorf U.S. Pat. No. 4,649,018. However, the particular problems associated with storage and transportation of ribbons of seed-like radioactive pellets useful in medical treatment are quite distinctly different from many of the problems encountered in storage or transportation of nuclear fuel elements or waste resulting therefrom.
Some devices for containing and exposing a capsule of radioactive material are known as disclosed in Meilink U.S. Pat. No. 2,862,108, and devices for applying therapeutic radiation originating from elongate lengths of beads or seeds of radioactive material which are located in passages within the device are known, as disclosed in Tokita U.S. Pat. No. 4,584,991. Furthermore, the assignee of the present invention has previously marketed containers for ribbons of medical dosages of radioactive materials, which containers first comprised a block of solid lead having a copper tube extending therethrough in which ribbons containing radioactive seeds could be stored and transported. Applicant later marketed a container comprising a stainless steel outer cylinder filled with solid lead and having a central tube and stainless steel carrier tubes extending through the length of the lead-filled cylinder. In one such embodiment the stainless steel tubes extended through the entire length of the lead filling having open exits at each end of the cylinder, with each such tube being marked with distinguishing indicia. Additionally, in that embodiment the open ended stainless steel tubes took a spiral path from one end of the container to the other about the central tube. In another somewhat similar embodiment, the stainless steel tubes were straight and terminated near one end of the lead filled cylinder which termination location was filled with a lead plug, while the other ends of the tubes were closed by a stainless steel plug. However, even those prior devices of the present applicant suffered disadvantages which are overcome by the invention disclosed and claimed herein.
The present invention also includes a unique retractable handle structure for the inventive storage and transportation containers for medical radioactive materials. While various retractable handles for various different articles and receptacles have been known in the art, as disclosed for example in Luebke U.S. Pat. No. 3,981,044; Gemeinder U.S. Pat. No. 1,220,975; McBrady U.S. Pat. No. 2,047,485 and Warner U.S. Pat. No. 3,522,955, the unique handle system of the present invention provides a structure and advantages which are different from and improvements over any presently known handle structure.
However, all of the foregoing prior methods of storing and transporting radioactive materials have substantial shortcomings, including the structure and manner in which handles are used in conjunction with such containers. In particular, such prior art structures and methods did not adequately address the safety issues involved in the storage and transportation of radioactive materials for medical purposes, and do not have adequate handle structures to provide proper safety and efficient storage of such containers.